Cooling plate for blast furnace inwalls and mantles



A. L. FOELL 2,345,188

COOLING PLATE FOR BLAST FURNACE INWALLS AND MANTLES March 28, 1944 2Sheetls- Sheet 1 Filed March 13, 1942 INVENTOR. noun/Li hen. {3&6 4.

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March 28, 1944. 2,345,188

COOLING PLATE FOR BLAST FURNACE INWALLS AND MANTLES A. L. FOELLFiledMarch 13, 1942 2 Sheets-Sheet 2 INVENTQR. LPHLFOEL ml: Irma/varPatented Mar. 28, 1944 UNITED STATES: PATENT OFFICE COOLING PLATE FORBLAST FURNACE INWALLS AND MANTLES Adolph L. Foell, Cleveland, OhioApplication March 13, 1942, Serial No. 434,468

8 Claims. I (01.122-6) This invention relates to the art ofmetallurgical blast furnaces, and particularly to those portions of suchfurnaces which rest on the mantle and extend thereabove' to form what isknown as the inwall.

nace it is extremely difficult to satisfactorily cool the mantle andinwall portions of the stack, and this is especially true when thefurnace is operated over a protracted period of time. reasons which willappear more fully hereinafter, these portions of the stack are soconstructed and arranged that they donot readily lend themselves toalteration in the manner of other portions of the shaft of the furnace.

It is among the objects of the present invention to more efficientlycool the inwalls and mantles of metallurgical blast furnaces.

Another object is the provision of a watercooled plate for the inwallsand mantles of metallurgical blast furnaces which is constructed andarranged for extreme durability in service.

Another object is to provide an instrumentality of the class describedwhich is characterized by increased resistance to displacement withrespect to that portion of the shaft of the furnace in which it isdisposed.

Still another object is to more securely connect the water-cooled'platewith the exterior of the furnace while at the same time permitting it tomove with the shaft during expansion and contraction.

The invention, then, comprises the features hereinafter more fullydescribed and as particularly pointed out in the claims, the followingdescription and the annexed drawings setting forth in detail a certainillustrative embodiment of the invention, this being indicative of butone of a number of ways in which the principles of the invention may beemployed.

In said drawings:

Figure 1 is a fragmentary horizontal sectional view through a portion ofeither the mantle or inwall of a metallurgical blast furnace employingthe cooling plates and associated instrumentalities of the presentinvention.

Figure 2 is an enlarged fragmentary horizontal view of the end of one ofthe cooling plates of Figure 1 illustrating the instrumentalities whichconnect it with the exterior of the furnace.

. Figure 3 is a, fragmentary sectional view take on the line IIIIII ofFigure 2. v

plate-.r neinbers which are so constructed and For 1 elevation taken online IX--IX of Fig. 1, and

arranged with respect to the jacket of the blast furnace as to permitrelative movement thereof for purposes which willbe describedhereinafter.

Figure 5 is an enlarged plan of one of the cooling plates of Figure 1,illustrating in more detail the construction therof.

Figure 6 isa view taken on the line VI-VI of Figure Sand illustrates anend of one ofthe cooling plates.

Figure '7 is a sectional view taken VII-VII of Figure 5.

Figure 8 is a view illustrating the outer ends of the water connectionsfor the cooling plates of the invention. l I

Figure 9 is an enlarged fragmentary sectional on the line illustrating aportion of the furnace stack with the cooling plate of the inventiondisposed in operative position therein.

Referring more particularly to the drawings,

the letter A designates either themantle or inwall portion of ametallurgical blast furnace,

'the same being referred to hereinafter as the stack. 26

This portion of the shaft of the-furnace is composed of very thickrefractory brickwork and is most frequently enclosed by a jacket B ofheavy metal plates.

According to conventional design, there is buried within the refractorybrickworkof the stack of the blast furnace at the time of its erection amultiplicity of hollow'water cooled plates, which are provided withwater intake and outlet conduits that extend to the exterior of thejacket B. These water intake and outlet conduits usually pass throughsmall round apertures in the jacket B, but the teachings of the presentinvention comprise enlarged apertures'C which may be rectangular inshape, and the purpose and intent of which will later become moreapparent. Usually there is provided between the stack A and encirclingjacket B a suitable packing D. Due to the fact that inwall or mantleplates are constructed and arranged for the circulation of cooling watercircumferentially of the very thick refractory brickwork of the stack,they are usually buried quite deep therewithin. By

plates, and having .no communication-with the their water intake andoutlet conduits, they cannot be removed and replaced without therebuilding of the stack. g

Early designs of inwall or mantleplates; which .tend to the exterior ofthe furnace.

reduced by extreme care in the casting technique,

there is ever present the possibility of a cracking at those pointswhere the integral elongated neck portions of the plate tendunderextreme'ly While blow holes and This tendency toward cracking atthe points mentioned is enhanced by reason of the fact that usually theintegrally cast elongated neck portions pass through small tightlyencompassing round apertures in the jacket B of heavy metal plates, andwhen the stack A moves during temperature change a binding action takesplace.

To a certain extent, the prior art stack plate described hereinbeforehas been replaced by those of more recent design which haveforeshortened integrally cast neck portions, or none at all, togetherwith separately attached water intake and outlet conduits which areenclosed by protection pipes extending from either the body portion ofthe plate, or the said foreshortened neck portions, to the exterior ofthe furnace.

high temperatures to move with the stackrelative to the jacket B,thereby subjecting the integral elongated neck portions to highlydestructive stresses.

Because of the foregoing difficulties which are indigenous to stackplates provided with integrally cast elongated neck portions, it becameprevalent: practice in case of a. failure to introduce through the waterconduits cement or the like, whereby the plate, having failed in itscapacity as acooling medium, was permitted to contribute somewhat to therefractory qualities of that portionofthe stack in which it wasdisposed.

As is well known to those skilled in the art, the

high temperatures of the furnace cause crumbling, spalling and fusion ofthe bricks comprising the walls of the inwall and mantle. .This

tendency toward disintegration is furthered by the reaction of thefurnace gases with the brickwork. The infiltration through therefractory brickwork of carbon monoxide (CO) gas within certaintemperature limits, reacts with the ferric oxide (F6203) of therefractory material. This reaction results in the formation of carbonwhich exerts an expansive effort in Zones heated to temperature within acertain critical range. In addition, the contact of the furnace burden(coke, ore and limestone) with the interior of the wall of the stackcauses much wear. These combined factors frequently cause thedeterioration of the interior of the wall of the stack to such an extentasto expose theinnerm'ostedge's of the stack plates therein.

"so long as a blast furnace is operated safely within the limitsprescribed by the thickness and construction of .the refractorybrickwork of the stack, the cooling plates therefore will remain buriedtherewithin. If, however, the furnace is operated over a protractedperiod of time, the

deterioration of the interior of the wall of the stack will progressbeyond the point where the innermost edges of the stack plates areexposed, with the result that ultimately the support for the said platesis destroyed.

When the deterioration of the refractory brickwork immediately below astack plate progresses to an extent sufficient to impair the supportafforded thereby, the extreme weight on the plate causes it to tend tosag down into the furnace,

.neck portion to crack at their points of connection with the bodyportions of -the plateis dan- 'ge'rously increased."

Some of these more recently designed stack plates jprovid'e flexibilityeither between the plate and the protection pipes or in the protectionpipes per'se whereby destructive stresses are greatly reduced if notentirely eliminated.

In accordance with the teachings of the present invention, there isprovided for disposal in the stack (either the inwall or mantle) of thefurnace a cast elongated relatively flat hollow cooling plate generallyindicated at 2. In plan, the cooling plate 2 is shaped like a segment ofa cylinder, the curvature thereof being such as will conform to thecontour of that portion of the stack in which it is, in the erection ofthe furnace, to be buried. The inner edge, and accordingly that which ismost adjacent the axis of the furnace, is therefore concave, as shown at3, while the opposite and outer edge is concentric and necessarilyconvex, as shown at 4.

Referring more particularly to Figures 2, 5 and 8 of the drawings, theplate 2 is provided at both of its ends with a foreshortenedright-angularly extending portion which is necked-in and provided on itsouter extremity with an integrally cast substantially flat terminalportion 1. 7 Both of these terminal portions 1 are shown as beingsubstantially oblong in plan and the most remote edges of each areprovided with a pair of ears 8. This construction and arrangementprovides a pocket 9 behind each pair of ears 8.

Referring more particularly to Figures 5, 6 and 8, it will be perceivedthat the outer face of each of the ears 8 is provided with a raised,flattened surface In for a purpose which will be later described.

Extending from the inner sides of the flat terminal portions 1 andlongitudinally of the interior of the stack plate 2 is a partition ll.Each of the terminal portions 1 has an aperture on either side of thepartition I I forming means for connecting an inlet or outlet pipe tothe plate, those at one end of the plate being designated 13, while theapertures at the opposite end of the plate are designated at Id. Theseapertures l3-l3 and I l-l4 permit of the ingress and egress of thecoolant (i. e. water) through conduits l5, and together withth'e'partitionmemher I I permit of inner and outer water circulatingpassages. In the event the plate 2 becomes optional, and as such formsno part of the present invention.

- Referring more particularly to Figures 1 through 3, the aperturesl3--l3' and 14-140:

the stack plate 2 are connected with water intake and water outletconduits l5 which extend to the exterior of the furnace.,

Extending between the foreshortened rightangularly extending necked-inportion 6 and in co-planar relationship with respect to the bottom ofthe plate 2 is an integrally castfin I! which is reinforced along itslength by a plurality of transversely extending integrally castreinforcing ribs l8 which connect with the convex outer surface 4 of theplate 2. The purpose of this reinforced integrally cast fin I1 is toprovide an increased bearing area, as shown in Figure 7, whereby thereis reduced the tendency of the plate to sag within the shaft of thefurnace upon the deterioration of the refractory brickwork immediatelybelow the said plate.

Referring more particularly to Figure 2, disposed to extend across eachof the terminal portions 1 is a metallic connecting plate 20 havingtherein a pair of apertures 2|, eachof which is aligned with one of theapertures (l3l3 and 14-14) which permit the ingress and egress of thecooling. water. Surrounding each of the apertures 2| (in the connecting.plates 20) is a protection pipe 22. These protection pipes 22 are weldedas at 23 to the respective connecting plates 20 and extend throughpassages P in the wall of the stack to the exterior of the furnace.

Preferably, the connecting plates 20 are of the same contour as theterminal portion 1 of the plate 2 to provide a flush relationship,;andthose portions of the connecting plates 2t!v which lie between the ears8 are apertured as at 24 to accommodate bolts 25 which extend from thepockets 9 and are provided on their outermost ends withthe usual nuts toprovide a rigid connection. It will be seen that the inner faces of theconnecting plates 20 contact the raised flat surfaces IU of the ears 8,and the clamping effect provided by the nuts 25 and their associatedbolts accomplishes an extremely rigid connection.

The teachings of the present invention comprise the securing cf theprotection pipes 22 to the jacket B of the furnace in such manner as tomaterially resist the inward longitudinal movement thereof, while at thesame time permitting trans-axial displacement in all directions. By thismeans there is reduced the tendency of the stack plate 2'to sag withinthe furnace upon the deterioration of the refractory brickworkimmediately below it, yet the said plate is free to move with the stackA during expansion and contraction accruing from temperature changeswithout subjecting either the protection pipes 22 or the water conduitstherewithin to. destructive stresses. More specifically, this part ofthe invention comprisesthe provision in the jacket B of the furnace ofenlarged apertures C which are shown as being rectangular in shape.Disposed between the inside of the jacket B and the packing D is arectangular plate 26 which overlaps the aperture C in the jacket and isprovided with a pair of apertures 21 for closely embracing theprotection pipes 22. This close embracing relationship prevents theegress of the packing D. Disposed exteriorly of the jacket B is a secondplate 23 which is shown as being identical in size and shape to theplate 26 which is described immediately hereinbefore. This plate 28 isprovided with apertures 29 which closely embrace the protection pipes22. However, while the plate 26 is free to slide along the protectionpipes 22, the plate 28 is welded to the said protection pipes in themanner of the continuous circular welds 23 which connect the inner endsof the protection pipes to the connecting plates 20.

The foregoing construction and arrangement is such as to permit of thesliding movement of the plates 26-28 with respect to the jacket B in anydirection, while at the same time restraining the inward movement of theprotection pipes 22 and the outward movement of the packing D.

Other modes of applying the principles of the invention may be employed,changes being made as regards the details described, providing thefeatures stated in any of the following claims, or the equivalent ofsuch, be employed.

I claim:

1. Ina metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a hollow cooling plate buried withinthe wall of said refractory stack whereby refractory portions of thesaid stack are provided between the inner and outer Walls thereof andthe said hollow cooling plate, the exterior wall of said stackhaving apair of passages communicating with said hollow cooling plate, fluidintake and fluid outlet connections for said hollow cooling plate, eachof said connections being in alignment with one of said passages andterminating inwardly of the exterior Wall of said stack, a protectionpipe disposed in each of said passages,

an apertured plate secured to the inner end of each of said protectionpipes, the apertures of said plates communicating with the bores of therespective pipes to which they are secured, means for securing saidapertured plates to said hollow cooling plate, and fluid inlet andoutlet conduits extending through said protection pipes into saidconnections. i

2. In a metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a hollow cooling plate buried withinthe wall of said refractory stack whereby refractory portions of thesaid stack are provided between the inner and outer walls thereof andthe said hollow cooling plate, the exterior wall of said stack having apair of passages communicating with said hollow cooling plate, fluidintake and fluid outlet connections for said hollow coolingplate, eachof said connections being in alignment with one of said passages andterminating inwardly of the exterior wall of said stack, 'a protectionpipe disposed in each of said passages, an apertured plate secured tothe inner end of each of said protection pipes, the apertures of saidplates communicating with the bores of the respective pipes to whichthey are secured, means for securing said apertured plates to saidhollow "cooling plate, fluid inlet and outlet conduits extending throughsaid protection pipes into said connections, and a balancing fin carriedby and projecting from said hollow cooling plate.

3. In ametallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a hollow cooling plate buried withinthe wall of said refractory stack whereby refractory portions of thesaid stack are provided between the inner and outer Walls thereof andthe said hollow cooling plate, the exterior wall of said stack having apair of passages communicating with said hollow cooling plate, fluidintake and fluid outlet connections for said hollow cooling plate, eachof said connections being in alignment with one of said passages andterminating inwardly of the exterior wall of said stack, a protectionpipe disposed in each of said passages, an apertured plate secured tothe inner end of each of said protection pipes, the apertures of saidplates communicating with the bores of the respective pipes to whichthey are secured, means for securing said apertured plates to saidhollow cooling plate, fluid inlet and outlet conduits extending throughsaid protection pipes into said connections, and a balancing fin carriedby and projecting from said hollow cooling plate, said balancingfinextending substantially toward the exterior of said refractory stack.

4. In a metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a metallic jacket for said stack, ahollow cooling plate buried within the wall of said refractory stackwhereby refractory portions of the said stack are provided between theinner and outer walls thereof and the said hollow cooling plate, theexterior wall of said stack having a pair of passages communicating withsaid hollow cooling plate, fluid intake and fluid outlet connectionsfor, said hollow cooling plate, each of said connections being inalignment with one of said passages and terminating inwardly of theexterior wall of said stack, a protection pipe disposed in each of saidpassages and connected to said hollow cooling plate, said protectionpipes extending through said metallic jacket, fluid inlet and outletconduits extending through said protection pipes into said connections,and flexible means connecting said protection pipe with said metallicjacket.

5. In a metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a metallic jacket for said stack, ahollow cooling plate buried within the wall of said refractory stackwhereby refractory portions of the said stack are provided between theinner and outer walls thereof and the said hollow cooling plate, theexterior wall of said stack having a pair of passages communicating withsaid hollow cooling plate, fluid intake and fluid outlet connections forsaid hollow cooling plate, each of said connections being in alignmentwith one of said passages and terminating inwardly of the exterior wallof said stack, a protection pipe disposed in each of said passages andconnected to said hollow cooling plate, said protection pipes extendingthrough said metallic jacket, fluid inlet and outletconduits extendingthrough said protection pipes into said connections, flexible meansconnecting said protection pipe with said metallic jacket, and abalancing fin carried by and projecting from said hollow cooling plate.

6. In a metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, a metallic jacket for said stack, ahollow cooling plate buried within the wall of said refractory stackwhereby refractory portions of the said stack are provided between theinner and outer walls thereof and the said hollow cooling plate, theexterior wall of said stack having a pair of passages communicating withsaid hollow cooling plate, fluid intake and fluid outlet connections forsaid hollow cooling plate, each of said connections being in alignmentwith one of said passages and terminating inwardly of the exterior wallof said stack, a protection pipe disposed in each of said passages andconnected to said hollow cooling plate, said protection pipes extendingthrough said metallic jacket, fluid inlet and outlet conduits extendingthrough said protection pipes into said connections, flexible meansconnecting said protection pipe with said metallic jacket, and abalancing fin carried by and projecting from said hollow cooling plate,said balancing fin extending substantially toward the exterior of saidrefractory stack.

7. A metallurgical blast furnace comprising a refractory stack, a hollowcooling plate buried in said stack and disposed wholly between the innerand outer walls thereof, said plate having openings therein throughwhich cooling liquid is adapted to pass, said stack having passagesextending inwardly from the outer wall thereof and in communication withsaid plate openings, a protection pipe in each of said passages, each ofsaid pipes secured at its inner end to said plate coaxial with anopening therein, fluid conduits disposed within said protection pipes incommunication with said plate openings at one end and projecting attheir opposite ends beyond the outer face of said stack Wall, andflexible means connecting said protection pipes with the outer face ofsaid stack wall.

'8. In a metallurgical blast furnace comprising a refractory stackextending above the mantle thereof, an apertured metallic jacket forsaid stack, an apertured hollow cooling plate buried in said wall insuch manner that refractory portions of said stack are provided betweenthe inner and outer faces thereof and the hollow cooling plate,

the said stack having a pair ofpassages therein communicating with theapertures in said jacket and said hollow cooling plate, fluid intake andfluid outlet conduits disposed in said passages and connected to saidhollow cooling plate and extending through the aperture in said metallicjacket, protection pipes enclosing said conduits, said pipes secured attheir inner ends to said cooling plate and extending through saidpassages to the exterior of said wall and through the aperture in saidjacket, a pair of apertured plates disposed one on each side of saidjacket and over the aperture therein, the said protection pipesextending through said apertures in said plates, one of said platesanchored in said wall and loosely receiving said protection pipes, andthe other of said plates having sliding engagement with said jacket andpermanently affixed to said protection pipes. I

ADOLPH L. FOELL.

